Analog-to-digital converters (ADCs) are widely used in electronic devices or systems such as cellular phones, tablets, computers, and many other electronic items. An ADC converts analog signals into digital signals (a combination of binary ones and zeros). An analog signal can be a signal obtained from antennae (e.g., in a wireless communication device), a microphone, or other sources. A successive approximation register (SAR) ADC is one of many types of ADCs. In some electronic devices or systems, designing an ADC, including SAR ADC, to meet overall operating criteria such as speed, noise tolerance level, and power consumption, may pose a challenge.